Composition of matter for furnace-linings or other purposes.



' absorption of the carbonic acid from the air UNITED STATES PATENT OFFICE.

-RUDOLF KECK, OF DENVER, COLORADO.

COMPOSITION OF MATTER FOR FURNACE-LININGS OR OTHER PORPOSES.

SPECIFICATION forming part of Letters Patent No. 648,756, dated May 1, 1900. Application died October 4, 1899- Berial No. 782,532. (No specimens.)

5 and useful. Composition of Matter for Fur:

nace-Linings or other Purposes, of which the following is a'iull, clear, and exact description. 7

My invention relates to the manufacture of a mineral substance suitable for basic furnace-linings and primarily intended therefor, but also capable of other applications, such as linings for architectural walls or filtering' purposes. 4

Basic linings for furnaces have generally been made in the form'of bricks .produced from magnesian'minerals, such as dolomite.

or magnesite. In the production of such bricks the minerals are burned and then the caustic material is mixed with a small percen tage' of a binder such as tar or clay or ferruginous loam or a solution of alkaline silicate, &c.,and then this mixture is burned at a very hi hheat. It is found, however, in practice t at it is impossible to mix the magnesian minerals thoroughly with a small proportion of materials mentioned. Bricks pr'epared in the manner described it not used immediately in the furnaces will begin to disintegrate after a few. days on account of by the caustic magnesia, while the caustic lime absorbs moisture and slakes, no matter how-high the pressure may have been. which was used in forming the bricks. The necessityof usingahigh pressure to form the bricks with such low percentage of binder is fur-- ther disadvantageous in that it increases the .heat conductivity of the finished article, and

this of course is detrimental, since it will cause the exterior of the furnace-converter to become dangerously hot while the interior is correspondingly cool. This results in a considerable increase of time required for the converting operation. These drawbacks of theordinaryfurnace-lining-namely,liability .tivity-.-are well known.

The object of my invention is to avoid these defects-,-that is, first to produce the mineral substance for the furnace-lining with the use of a moderate pressure only, so as to avoid the high density and heat conductivity resulting from the application of a very high pressure. On the other hand it has been my aim to find a material adapted for use as a flux or hinder which could be used in large proportions with the magnesian minerals without any liability of subsequent disintegration. For this purpose I employ as a flux or hinder the substance found along the eastern foot-hills of the Rocky Mountains, and- I may use the whole material of the shale constantly occurring there in the Jnra-Trias of the Mesozoic period. This material consists chiefly of thirty to fifty percent. of silica and forty to fifty-per cent. of alumina and oxids of iron,-

while the rest consists of carbonates of magnesia and lime. This material has valuable chemical and physical properties for the purpose of my invention and may be used 5 net as it is obtained by pick and jsho'vel, the only operation "preparatory to mixing it with the magnesian'materialbein g crushing'it to a fineness of an eighteen 'or twenty mesh sieve.

Tlxe'p'roportion in which the binder or flux is to be mixed with the magnesian material depends on the percentage of 'the magnesium oxid and calcium oxid contained in said magnesian material. I have found that the best proportion is to use five pounds ofcrushed flux to seven pounds of magnesium oxid and calcium oxid contained in the magnesian material. of the magnesium oxid and calcium oxid con- In other words, if nis the percentage 8 V tained in the magnesian material a hundred= pounds of said material will have tobemixed with five-sevenths times 11 pounds of crushed flux; The mixture is formed into bricks in the ordinary .manner, the pressure used not being greater than that obtained with the common fire-brick handpress.- The bricks are then burned in the ordinary fire-brick furnace. The resulting product is a porous stone or brick which is hard and strong,which will not slake when exposed tomoist air, and I will not c'rumble'atter being usedin a fur.- nace. The stone or brick on account of its porosity is a comparatively-bad conductor of heat and capable for the same reason of absorbing a considerable-amount of phosphoric acid during the basic-steel process. When the bricks are intended for the latter process, I may slightly increase the proportion of the magnesian material in about the proportion of two-pounds of crushed flux to three pounds of the maguesian material.

As the artificial stone produced in the manner above described is fireproof and comparatively light, it aifords a good material for liningthe walls of buildings, and owing to its low conductivity'of heat it actsas a heatinsnlator. The porosity of my improved arti ficial stone makes it adapted for use in filters vand the like.

Having thus described my invention, I claim as new and desire to secure by Letters Patentp 1. The herein-described artificial stone, consisting of a magnesian material, and a hinder or flux-consisting of the material of Mountains, said stone being porous ands bad the shale constantly occurring in the Jura- Trias along the eastern foot-hills of the Rocky conductor of heat.

2. The herein-described artificial'stone, consisting of, a magnesian material, and a hinder or flux consisting of the material of S the shale constantly occurring in the J ura- Trias along the eastern foot-hills of the Rocky Mountains, in the proportion of about two parts of flux to three parts of magnesium oxid and calcium oxid contained in the magnesian material.

RUDOLF KECK. \Vitnesses:

W. II. MARSH, A. H. LOMAX. 

